


Mucky Pup

by Fr333bird



Category: Teen Wolf (TV)
Genre: Established Relationship, Licking, M/M, Oral Sex, Public Sex, Underwear Kink
Language: English
Status: Completed
Published: 2012-10-24
Updated: 2012-10-24
Packaged: 2017-11-16 23:29:00
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 4,367
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/545005
Author URL: https://archiveofourown.org/users/Fr333bird/pseuds/Fr333bird
Summary: <blockquote class="userstuff">
              <p>Derek disapproves of Stiles’ baggy boxers so he takes him underwear shopping.  </p><p>  <i>Stiles just stands and stares, his mouth dropping open in that way that makes Derek want to fill it. “I had no idea there was this much underwear in the world,” he says, shaking his head in disbelief.</i></p>
            </blockquote>





	Mucky Pup

**Author's Note:**

  * For [goldncuffs](https://archiveofourown.org/users/goldncuffs/gifts).



> Written for a twitter prompt from TwistedInMasen. I hope I did it justice, it was such a fun idea. Somewhere along the way this story turned into an ode to Stiles’ testicles. I’m not sorry.  
> Thanks to my lovely pre-readers Beckybrit and Donnersun, and to Fardaresmai2 for a short notice beta.

“Okay, I seriously have to go now or I’m gonna be late for school.” Stiles drags himself out of Derek’s bed and flails around looking for clothes. “Mornings suck so hard. You’re just going to go back to sleep as soon as I’m gone aren’t you? That’s so unfair, dude.”

“Yep,” Derek rolls onto his back into the warm patch left by Stiles and stretches luxuriously, his morning wood tenting the sheets. “I might have to jack off first though, seeing as you’re leaving.”

“I hate you.” Stiles grumbles as he turns his back on Derek, but his voice is soft and Derek smiles.

He watches as Stiles pulls his boxers up until they rest on his slim hips. They come down to mid thigh and Stiles is lost in the baggy plaid fabric. Then he bends to pick up his jeans. “Eww! What the fuck?” He pushes the boxers off again as Derek watches in amusement. He manages to keep a straight face while Stiles examines the large wet, sticky patch on the back of the blue and white cotton shorts. “What is this? It can’t be jizz because you never waste that.”

It’s true; Derek is a fan of the licking. It’s a wolf thing, he assumes. It’s _definitely_ not something he’s prepared to discuss with the rest of the pack to find out if they’re the same, but Derek loves licking Stiles clean after sex. Seriously, he can’t get enough of it, and Stiles seems to be happy with the arrangement.

“It’s lube,” Derek explains. “I spilled some last night and your shorts were the first thing I grabbed.”

“Well I need to borrow some underwear then, because I have gym class today and I’m so not going commando in the locker room. Jackson would have a fucking field day with that.”

“Left-hand top drawer,” Derek informs him.

Stiles rummages around for a minute. “Seriously, dude. No boxers at all? Not even an old ratty pair lurking somewhere?”

“I never wear them.” Derek shrugs as he replies. “I like my junk to feel supported. You should try the royal blue briefs, they’re a little small on me, so they should fit you okay.”

Stiles ferrets about in the drawer again. “Jesus, you have a ridiculously huge collection of underwear. How did I not notice this before? It’s like some weird fetish. Seriously, you have like every color possible.”

Derek doesn’t deny it; the evidence speaks for itself. But there’s nothing wrong with liking nice underwear, and it’s his only extravagance really. The insurance payout on the house has left him with more than enough to live on, and his new apartment is pretty basic. He wears the same two pairs of jeans and his black leather jacket all the time and only owns a few t-shirts. Underwear is Derek’s weakness -- not that he sees it as a weakness of course, it’s just an expression.

“Okay, found ‘em.”

Derek watches as Stiles steps into the briefs and pulls them up. The wide black elastic waistband at the top snaps into place with a satisfying sound that makes Derek’s dick tingle and fill even more. Stiles stoops to gather the rest of his clothes from the floor, his back to Derek, then straightens up. Derek casts appreciative eyes over Stiles’ pert buttocks, the curve of his lower back, the slim strength of his thighs. “Turn around, I wanna see how you look in them.”

Stiles turns and looks at him disbelievingly. “I don’t have time for this.”

“Just looking, Stiles. No touching.” Derek runs his eyes hungrily over Stiles’ pale skin, down over his lean torso to the snug, blue briefs that he’s wearing. “They look good on you.” Derek’s hand is on his cock under the sheet now, squeezing and stroking. Stiles’ eyes drop to the movement.

“I _really_ hate you.” Stiles’ cock is visibly filling through the thin, stretchy material now. He adjusts himself, glaring at Derek. “Now I have to drive to school with a boner.”

“I guess so.”

Derek doesn’t stop. He keeps jerking himself off as Stiles dresses, stopping to watch Derek distractedly now and again. When he’s finally ready he sits on the edge of the bed and pulls back the sheet to look at Derek’s hand moving on his cock. “Yep, it’s official. I hate you so much right now.” But his lips are curved in a smile and his eyes are dark as he leans down to kiss Derek’s mouth, a quick slide of tongue between Derek’s lips that are parted and slack with arousal. Derek kisses him back and strokes himself harder, getting close.

Stiles pulls away reluctantly and stands. “See you later.” He rolls his eyes at Derek who smirks back. And then Stiles is gone. The door closes behind him, and Derek spills onto his fist and stomach with a growl, his fingers teasing the last drops of come from his cock as his body arches into the pleasure. He scoops his come off his belly and licks his fingers clean. Then he curls around his Stiles-scented pillow and goes back to sleep for a while.

xOx

He texts Stiles on Saturday morning.

**Get up, get dressed. I’m taking you shopping.**

Stiles stayed at his own house last night. He can’t get away with claiming sleep-overs at Scott’s more than a couple of times a week. Derek would like Stiles in his bed every night if he had his way, but the Sheriff has a gun. And Even though the bullets in it aren’t made of wolfsbane, getting shot still hurts like a bitch and is kind of inconvenient.

Stiles replies pretty quickly considering it’s 9am on a Saturday.

**You’re what now???**

**Taking you shopping. I’ll pick you up in half an hour.**

Stiles doesn’t reply again, so Derek takes that as tacit acceptance.

When he knocks on Stiles’ door, it’s the sheriff who answers. “Good morning, Hale.” He eyes Derek with suspicion.

“Morning, sir,” Derek replies, meeting his eyes and forcing a smile.

He can smell the distrust and suspicion coming off the man in thick, disconcerting waves. Derek isn’t easily intimidated, for obvious reasons, and he rarely cares enough to want to win anybody’s approval, but it would make his life a whole lot easier if the Sheriff had a better opinion of him. Stiles’ father has come to accept that Derek is someone who Stiles hangs out with sometimes, but he clearly still has reservations. Derek makes a mental note to ensure that Sheriff Stilinski doesn’t find out about all the underage sex that Stiles is having with Derek anytime soon.

Stiles appears behind him, shrugging into his jacket and grinning at Derek over his dad’s shoulder. Derek resists the urge to grin back too widely, luckily he’s good at deadpan. “Hey, Stiles,” he says casually.

“So, where are you boys off to?” Derek’s eyes flick back to the man in front of him and Derek holds his challenging gaze. He doesn’t think that he imagined the slight emphasis on the word boys. It’s another subtle reminder to Derek that Stiles is younger than him. It feels as though it’s calculated to make Derek uncomfortable, to imply that he and Stiles don’t fit together as friends, and definitely not as more than friends.

“Going shopping, apparently,” Stiles says breezily as he shoulders past his father, giving him a friendly slap on the back. “See you later, Dad.”

“Shopping.” Sheriff Stilinski manages to inject the word with a perfect balance of disbelief and disapproval. “Okay then.”

“‘Bye, Sheriff.” Derek turns away. The hair on the back of his neck prickles. He can practically feel the sheriff’s eyes on him as he and Stiles walk to the car.

“So where exactly are we going?” Stiles asks as they pull onto the freeway. “I assumed we were just going into town.”

“I’m taking you to the city,” Derek replies, putting his foot down as he pulls past a slow truck and settles back in the seat of the Camaro. “Did I forget to mention that part?”

“Uhm... yeah.” Stiles’ voice is curious. “Lucky I got my homework done last night then. But why?”

“You’ll see.”

xOx 

The drive is a couple of hours long. Stiles drives Derek insane by fidgeting, fiddling with his stereo and badgering him constantly about where they’re going. Derek growls and tells him intermittently to ‘ _fucking sit still,_ ’ and ‘ _keep your hands to yourself, Stiles._ ’ But he secretly enjoys it.

They find a space in the crowded parking lot, and Derek leads Stiles through the streets. He takes long strides but Stiles matches them, looking around himself curiously at the colorful shops and the eclectic mixture of people in the busy streets. Derek guesses that Stiles rarely visits the city, he can’t imagine the Sheriff having much call for traveling this far to shop. He looks like more of a catalog man. Of course, they could have just shopped online for what Derek has in mind, but he figures that this way will be far more entertaining.

He watches the realization dawn on Stiles’ face as they pause outside the store.

“Oh no,” Stiles rubs a palm over his fuzz of dark hair as he looks at the window display. It consists of a collection of golden male torsos clad only in underwear. There’s a variety of colors and styles and shapes, but they’re all perfectly fitting over the impressive molded bulges, and probably seriously expensive. A washing line is strung up across the top of them, with rainbow colored fairy lights twined around it. More pairs of underwear are pegged onto it with bright pink plastic clothes pegs. Boxer briefs, briefs, jocks and even some alarming looking pouches held together by too-thin string. But there’s no sign of any of the baggy cotton boxers that Stiles usually prefers. “No way.” He looks like an animal in a trap, eyes wide with alarm.

“Yes way,” Derek grabs his hand and hauls him over the threshold.

Stiles just stands and stares, his mouth dropping open in that way that makes Derek want to fill it. “I had no idea there was this much underwear in the world,” he says, shaking his head in disbelief.

“Can I help you gentlemen?” A blond assistant sidles up to them. His perfect white grin stays in place as he blatantly checks them both out. The grin widens slightly; he obviously approves of what he sees.

Derek moves a little closer to Stiles and grips his hand more firmly. “We’re just looking for now, thanks. But we might want to try some stuff on in a while, if that’s okay?”

“Of course,” the assistant replies smoothly. “My name’s Sam. Just give me a shout if you need any help with sizing.” His eyes drop to Derek’s crotch for a moment and he smiles again before turning and leaving them to it.

Stiles is unusually silent, still staring goggle-eyed like a kid in a candy store. There are huge posters on the walls of models showing off the different designs available. Their smooth, toned bodies and the interestingly-shaped bulges have Stiles practically drooling. Derek squeezes his fingers so tightly that he yelps, then snaps his attention back to Derek.

“Come on,” Derek says. “I think you need size small.”

“I do not,” Stiles protests. “I always wear a medium.”

“And your boxers hang off your ass and come down to your knees.” Derek rolls his eyes. “You’re trying smalls.”

“You’re so bossy.” Stiles mutters. “Is that an alpha thing? Or just a you-being-a-pain-in-the ass thing?”

Derek ignores him and starts selecting underwear from the items laid out on display.

“Do I get an opinion here?” Stiles asks, peering over Derek’s shoulders as a pair of fuchsia pink boxer briefs get added to the ever-growing pile over Derek’s arm. “Pink? Really?”

“I think your ass will look good in pink. And no, you don’t. Your taste in underwear sucks hairy balls.”

“You like sucking balls.” Stiles’ hands are on Derek’s waist now, warm and teasing as they creep under his jacket and t-shirt to graze the skin of Derek’s hips.

Derek refuses to be distracted from his task, even though the touch of Stiles’ hands and the thought of his balls in Derek’s mouth is making his dick start to thicken. “Your balls are barely even fuzzy,” he points out, moving along the display of underwear, twisting away from Stiles’ caress.

“Oh cool, superhero undies. I want the Batman ones.” Stiles darts across to a different stand and grabs a pair of black and yellow boxer briefs with the unmistakable logo on the front.

“Just make sure you get the right size,” Derek advises, smirking to himself as Stiles grumbles something under his breath about ‘bossy, fucking werewolf boyfriends’ and puts down the pair in his hand; presumably so he can rifle through the piles to find a small.

Once Derek is satisfied that they have enough for Stiles to try, he jerks his head toward the fitting rooms at the back of the store. “Get your ass in there.” He grins unashamedly as Stiles glares at him.

“So, you’re just gonna dress me up like a Ken doll huh?”

“Yep,” Derek nods. Then he turns to Sam who’s been watching their exchange with amusement and undisguised envy. “Okay if we go in together?”

“Sure.” Sam flutters his eyelashes at Derek. “But he needs to keep his own briefs on underneath the merchandise.”

“But I’m wearing boxers,” Stiles protests. “That’s really not gonna work at all.”

“It’s okay,” Derek assures him. “I brought that blue pair.”

“I love a man who thinks of everything,” Sam sighs. “Is he this perfect all the time?”

Stiles just rolls his eyes while Derek chuckles. “This controlling, you mean? You have no fucking idea.”

The changing room that Sam shows them into is large. There’s plenty of room for the two of them, and there’s even a red leather armchair in the corner that matches the thick curtain over the door. The walls are lined with full length mirrors on hinges that pull out, so that it’s possible to see yourself from every angle.

Sam closes the curtain, carefully pulling it so that it overlaps the edge of the door frame. “Have fun, boys.” He sounds a little wistful. “And just call me if I can help with anything, anything at all.”

Stiles narrows his eyes once the assistant has left. “He’s totally into you.”

Derek shrugs. “Well unfortunately for him, I’m totally into _you_.” He holds Stiles’ stare and watches with satisfaction as his honey-brown eyes darken and his cheeks flush pink. “Now, strip. You’ve got underwear to try on.” He dumps his armful on the low bench, then sits himself comfortably in the armchair and waits.

When Stiles is down to his offending boxers he looks at Derek, hesitating. Derek just jerks his head. “Carry on.” He’s enjoying this. “You can’t try decent underwear on over those monstrosities.”

“Jeez, you’re such an underwear snob.” Stiles scowls as he pushes his boxers down to reveal his soft cock in its dark patch of trimmed pubes. His perfectly symmetrical, almost hairless balls hang beneath and Derek’s mouth waters as he looks at them.

Stiles stands before Derek naked and waits expectantly. His cock begins to plump up a little as Derek watches it. Derek can smell the sweet, warm scent of Stiles’ skin as it fills the small space, the musk of his cock and balls, the tang of his sweat. Derek’s dick is a thick line in the leg of his jeans now. He adjusts it as he stares at his boyfriend.

“Derek.” Stiles' voice is impatient. “The blue briefs?”

“Oh yeah, sure. Sorry.” Derek gets with the program and fishes them out of his jacket pocket and tosses them to Stiles who catches them deftly.

Stiles slips them on, adjusting his junk and making a face. “It feels weird having my balls all snug like this.”

“They look good though.” Derek eyes him hungrily, the stretchy lycra fabric cups Stiles’ cock and balls so closely that Derek can see the perfect rim of his cockhead, and the plummy roundness of each testicle nestled beneath. He palms himself through his jeans, pulling his hard cock up to rest in the crease where his thigh meets his body.

“Quit ogling me or I’ll end up with a boner.” Stiles moves close enough to flick Derek’s ear. Derek growls and feels his eyes flare red. Stiles is unmoved by the display of aggression. “Shut up, Sourwolf,” he teases. “Tell me what to try on first.”

The next fifteen minutes or so are delicious torture for Derek, as Stiles parades in front of him in an assortment of different underwear.

Stiles is self-conscious at first. He’s never understood what Derek sees in him. He’s always been bewildered by the attraction because he’s utterly blind to his own appeal. He sees himself as geeky and awkward, cute on a good day maybe, but he’s unable to accept himself as sexy. To Derek that’s all part of his appeal. Derek isn’t good with words, but he believes that actions speak louder. And since they’ve been together Derek has made it his mission to break down the barrier of Stiles’ insecurity, and show him over and over again how much he wants him.

Today is another example of this. At first Stiles is nervous and blushing, wrinkling his nose at his own reflection. But his eyes keep flickering to Derek’s hand that’s resting on his erection, squeezing himself through the material as his arousal builds. Stiles sees it, and he must know that Derek’s thinking about doing dirty, dirty things. Stiles’ eyes get darker and his nipples tighten and he slowly begins to move with more confidence, posing for Derek in each new pair of briefs that he tries on.

“So, does the pink work for you then?” Stiles moves close, turns his back to Derek and looks over his shoulder, wiggling his ass.

The pink definitely works. The fuchsia pink boxer briefs are tight and snug. The line of the blue briefs beneath spoils the effect a little, but the color is perfect against Stiles’ pale skin.

“Turn around,” Derek can feel the roughness of his voice in his throat. His dick twitches in his jeans and leaks onto his thigh.

Stiles turns, moving closer still, until he’s standing between Derek’s knees. Stiles is hard now, his erection curving up and sideways, trapped in two layers of stretchy cotton-lycra. Derek can smell his excitement, a heady blend of teenage hormones and salty-musk. He puts his hands on Stiles’ hips, strong fingers curling into the meat of Stiles’ ass, and he pulls him forward slowly.

“Dude.” Stiles sounds uncertain. The flush of his cheeks echoes the color of the underwear. “You really gonna do this here?”

It suddenly seems very quiet in the dressing room. The rasp of their breathing punctuating the time as it stretches out. There’s the muted sounds of voices from the front of the store -- Sam’s busy charming more customers -- and Derek’s sensitive ears can pick up sounds from the street. Traffic and humanity, passing by in a chaos of distant noise.

“Yes,” he replies simply, squeezing tighter.

Stiles makes a little sound of distress, and the sharp scent of precome invades Derek’s senses. “Fuck,” Stiles mutters. “We’ll be buying this pair then.”

The sight of the wet patch, blooming and spreading at the tip of Stiles’ cock is the last nail in the coffin of Derek’s tenuous self-control. He growls, a deep low rumble in his chest that vibrates through him like distant thunder. And then he’s pulling hard, and Stiles is scrambling into Derek’s lap, and everything outside the dressing room is forgotten, because Derek needs to taste Stiles and nothing else matters.

Derek pulls both pairs of underwear down, just enough so that he can get to what he wants. The elastic pushes Stiles’ balls up obscenely and his cock is flushed pink and leaking. Derek shuffles lower so that he can get his mouth on it, sucking Stiles down with no preamble.

“ _Jesus_.” Stiles gasps. He’s hot against Derek’s tongue and the sweet-salt taste explodes in Derek’s mouth.

Derek releases him with a filthy slurping sound and licks down Stiles’ shaft, but the angle is awkward and he can’t get where he wants to be. He growls -- in frustration this time -- and lifts himself up up. He takes Stiles with him effortlessly, and flips him over so that Stiles is now the one spreadeagled in the armchair. “Derek,” he whimpers as Derek kneels between Stiles’ legs and pushes his thighs even wider.

Stiles is like a meal waiting to be sampled; he looks amazing and he smells even better. His balls are high and tight, even without the waistband pushing them up. Derek leans in, nuzzling them as he breathes in deeply. Of all the incredible scents that makes up the flavor of Stiles, this is Derek’s absolute favorite. The musky sweetness around his sac makes Derek feel dizzy with desire. He feels the ripple of the wolf under his skin and forces it down. He has no wish to explain a shredded sofa to the sales assistant when they finally leave the changing room. It’s going to be awkward enough already, but Derek doesn’t really give a shit about that.

He uses his tongue now, lapping at the textured skin, feeling it ripple under his tongue as Stiles moans and twists his fingers into Derek’s hair. Stiles’ scent is making saliva flood into Derek’s mouth and it’s messy. Derek lets it dribble out, making Stiles’ balls wet as he laps at them like the animal he is. He brings a hand up, using the spit that trickling behind to slick his way as he forces his fingers back, hampered by the tight elastic. When he reaches the sensitive skin around Stiles’ hole, Stiles jerks and curses, his cock drooling precome.

Derek moves back up to suck on Stiles’ cock for a while, teasing his entrance with a circling finger as he takes him deep.

“ _Fuck_... Derek, such a fucking tease...” Stiles hisses, obviously trying to be quiet.

 _Fuck that_.

Derek wants people to hear them. He wants people to hear Stiles yelling for him.

He lets his finger press inside like he knows Stiles wants. But at the same time he takes his mouth away from Stiles’ dick, and goes back to focus on his testicles again making Stiles groan with frustration. Derek grins and ignores him, sucking one of them into his mouth as he forces a second finger in, then goes back to licking. He curls and pumps his fingers in and out a few times as his tongue strokes Stiles’ balls.

Stiles comes with no warning. Derek feels his muscles tighten and the rhythmic pulse around his fingers as Stiles shoots, body jerking as he lets out a stifled cry. His first spurt hits his belly and the second spills down his cock, a splash catching Derek’s cheek. Derek sucks Stiles’ cock into his mouth and catches the last drops as he carries on fucking Stiles with his fingers.

As soon as Stiles has finished, Derek drags his fingers out making Stiles wince. He unbuttons his jeans frantically, and pulls his cock out, desperate for release. He moves up, kneeling astride Stiles and feeds his cock into Stiles’ willing mouth. Stiles has had plenty of practice at this by now, and he knows exactly how to get Derek off quickly. Derek concentrates on not wolfing out while he fucks into the heat of Stiles’ mouth; but when he comes, it’s with a growl that’s definitely verging on the not-human. Stiles swallows every drop of Derek’s come and sucks him clean until Derek pulls away, leaving Stiles slack jawed and flushed, goofy with post-sex euphoria.

“Jesus, Derek. Was this your plan all along when you brought me shopping?” He grins. “Because I’m totally okay with this kind of shopping trip, just so you know.”

“Not really,” Derek replies, and it’s the truth. He hadn’t thought beyond the part where it would be fun to get Stiles half-naked in a dressing room and buy him some cool new underwear. He hadn’t really thought it through at all, otherwise he would have known where this would end up.

“You left a mess,” Stiles remarks, looking down at the sticky white spots now cooling on his belly. “Mucky pup.”

Derek raises an eyebrow. “What did you just call me?”

“You heard,” Stiles smirks. “Now clean me up.”

Derek sniffs his disapproval. But he never lets good come go to waste, and they don’t have any tissues anyway. When he’s finished licking Stiles clean, Stiles pats his head. “Good boy,” he says, an evil glint in his eye.

“Don’t push your luck.” Derek glares at him.

They sort out which styles they’re buying and which ones they’re not before they leave the dressing room. The pink boxers are a lost cause. They stink of sex and are soaked with spit and jizz. Stiles is all for hiding them in a pocket. But Derek figures that Sam’s a smart guy. What with the amount of time they spent in the fitting room, Stiles’ pink cheeks and the noises that they were making, there’s no way he doesn’t know they were up to something.

“He’ll be jerking off thinking about us later,” Derek says, as he shrugs away Stiles’ protests. “I’ll just pay for these ones too.”

Sam eyes them both with a very knowing expression as they approach the counter with their intended purchases. But he doesn’t speak as he rings the items up, and folds and bags them carefully.

Derek keeps the pink ones till last, then he pulls the tag off them and hands it to Sam so he can scan the barcode while Derek keeps them in his hands. They reek. Even Sam’s human nose can probably smell the bleachy spunk-smell. “I’ll have a separate bag for these ones please.”

“Of course sir,” Sam smirks. “No problem at all.”


End file.
